It is used for hand or random orbital sanders. It is for either wet or dry application, i.e. dry sanding on wood or wet sanding/buffing on automobiles/airplanes. It is most commonly used for metal working applications and final lacquered wood sanding. Silicon Carbide is next to diamond in hardness, Silicon Carbide, characterized by its sharp sliver like grains makes it superior for its ability to penetrate with light cutting pressures. It is primarily used for grinding nonferrous materials such as brass, copper, bronze and aluminum. Other applications of Silicon Carbide include grinding of glass, wood, rubber and plastics. It is used also to finish polyurethanes, primers, lacquers and sealers. Silicon Carbide is the grain of choice for certain finishes on stainless steels. Silicon Carbide products are typically black in color.